1. Field of the Invention
The present invention relates to a chip embedded printed circuit board and a manufacturing method thereof; and, more particularly, to a chip embedded printed circuit board to form upper patterns connected to posts on an insulating layer and to form lower patterns by etching a copper foil after forming the insulating layer embedding a chip provided with the posts over the metal foil and a manufacturing method thereof.
2. Description of the Related Art
Recently, an electronic part has become high density and high performance to meet the needs of high performance and miniaturization of an electronic device. Therefore, the demand for a small-sized printed circuit board capable of mounting the electronic parts at high density is gradually increasing. In response to this demand, development of a multi-layer circuit board for electrically connecting wirings formed on different layers or the electronic part and the wiring through a via hole is proceeding.
Such a multi-layer circuit board can realize a high-density wiring as well as reduce the wiring for connection between the electronic parts. In addition, it can not only increase a surface area of the printed circuit board but improve an electrical characteristic by mounting the electronic part.
Particularly, since in an embedded printed circuit board inserting an electronic part into a substrate, the electronic part is not mounted on the surface of the substrate but embedded inside the substrate, miniaturization, high density and high performance of the substrate can be achieved and thus the demand thereof is gradually increasing.
In a conventional chip embedded printed circuit board, a chip is positioned after a perforated core substrate is attached to a tape and the tape is separated after laminating an insulating layer, e.g., a prepreg layer on a surface opposite to a tape-attached surface. Thereafter, the prepreg layer is also laminated on a surface on which the tape is separated.
Then, a via hole is formed at a position needing electric connection by a laser drill method, or the like and a copper plating process or the like are performed.
However, it is difficult for the conventional chip embedded printed circuit board embedding the chip by using the tape inside the perforated core substrate to reduce the entire thickness of the substrate. Further, in case that the via hole is formed by the laser drill method or the like, it is difficult to process the via hole at an exact position due to a position tolerance of the chip or a tolerance of laser drill, which cause a connection failure, thereby deteriorating yield and reliability.